title: MicroRNA-302b suppresses cell proliferation by targeting EGFR in human hepatocellular carcinoma SMMC-7721 cells.
abstract: BACKGROUND
  MicroRNAs are regulators that can play an essential role in tumorigenesis. Although miR-302 families have been suggested to be tumor repressors in human cancer, the mechanism by which they suppress tumor development remains to be defined. In this study, we discover that miR302b suppresses tumor proliferation may due to directly targeting EGFR in human hepatocellular carcinoma (HCC).
  
  
  METHODS
  QRT-PCR was used to assess miR-302b and EGFR expression in 27 pairs of clinical hepatocellular carcinoma tissues and their corresponding adjacent nontumorous liver tissues. MTT, colony formation, immunofluorescence staining, and cell cycle assays were used to examine the tumor suppressor role of miR302b in cell proliferation. Luciferase assays were performed to assess the EGFR was a novel target of miR-302b. Western blot assay was used to validate the protein expression level.
  
  
  RESULTS
  We demonstrated that miR-302b was frequently down-regulated, whereas EGFR was up-regulated in 27 pairs of clinical HCC and non-tumorous counterparts. The dual-luciferase reporter assays revealed that EGFR was a novel target of miR-302b. Re-expression of miR-302b resulted in the inhibition of proliferation in hepatocellular carcinoma SMMC-7721 cells. The silencing of EGFR by miR-302b or siEGFR led to down-regulation of proliferation-related proteins, such as AKT2, CCND1, and CDK2.
  
  
  CONCLUSIONS
  miR-302b suppresses HCC growth may due to targeting the EGFR/AKT2/CCND1 pathway.
authors.affiliation: Department of Genetics and Molecular Biology, Xi'an Jiaotong University Health Science Center, No,76 West Yanta Road, Xi'an, Shaanxi 710061, P,R, China. hchen@mail.xjtu.edu.cn.
authors.forename: Lumin
authors.initials: L
authors.lastname: Wang
authors.forename: Jiayi
authors.initials: J
authors.lastname: Yao
authors.forename: Xin
authors.initials: X
authors.lastname: Shi
authors.forename: Lili
authors.initials: L
authors.lastname: Hu
authors.forename: Zongfang
authors.initials: Z
authors.lastname: Li
authors.forename: Tusheng
authors.initials: T
authors.lastname: Song
authors.forename: Chen
authors.initials: C
authors.lastname: Huang
mesh_terms: D020029:Base Pairing; D001483:Base Sequence; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference
chemical_list: C532169:MIRN302A microRNA, human; D035683:MicroRNAs; D066246:ErbB Receptors